fix domain validator

backend/middleware/domainValidator.go

@@ -1,6 +1,7 @@
 package middleware
 
 import (
+	"net"
 	"net/http"
 	"strings"
 
@@ -9,7 +10,10 @@ import (
 
 func DomainValidator(domain string) gin.HandlerFunc {
 	return func(c *gin.Context) {
-		host := strings.Split(c.Request.Host, ":")[0]
+		host := c.Request.Host
+		if colonIndex := strings.LastIndex(host, ":"); colonIndex != -1 {
+			host, _, _ = net.SplitHostPort(c.Request.Host)
+		}
 
 		if host != domain {
 			c.AbortWithStatus(http.StatusForbidden)